Re: [PATCH v2 05/10] Use clock_gettime to implement time.

[Florian Weimer <fweimer at redhat dot com>]

* Paul Eggert:

> Florian Weimer wrote:
>> Given that time has no stringent accuracy requirements, this shouldn't
>> come as a surprise.
>
> In what sense does 'time' have less-stringent accuracy requirements
> than clock_gettime (CLOCK_REALTIME) does? Can 'time' return a value
> that disagrees with the time_t part of what clock_gettime
> (CLOCK_REALTIME) returns? Any such disagreement would cause
> application bugs that could well be unlikely and hard to track down;
> also, if there is disagreement, replacing calls to 'time' with calls
> to clock_gettime might not be advisable even aside from performance
> issues.

Maybe accuracy is the wrong word.  But time can definitely return the
value of a variable that is incremented periodically from the timer
interrupt.  That's not possible for gettimeofday or clock_gettime with
CLOCK_REALTIME (from a quality-of-implementation perspective).

Thanks,
Florian